package com.wyy.image;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;

import javax.imageio.ImageIO;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder; 

public class NarrowImage {
	/**
	 * @param im
	 * 原始图像
	 * @param resizeTimes
	 * 倍数,比如0.5就是缩小一半,0.98等等double类型
	 * @return 返回处理后的图像
	 * 
	 */
	
	public BufferedImage zoomImage(String src) {
		BufferedImage result = null;
		try{
			File srcfile = new File(src);
			if (!srcfile.exists()) {
				System.out.println("文件不存在");
			}
			BufferedImage im = ImageIO.read(srcfile);
			/* 原始图像的宽度和高度 */ 
			int width = im.getWidth();
			int height = im.getHeight();
			
			//压缩计算 
			float resizeTimes = 0.3f; 
			/*这个参数是要转化成的倍数,如果是1就是转化成1倍*/ 
			
			/* 调整后的图片的宽度和高度 */ 
			int toWidth = (int) (width * resizeTimes); 
			int toHeight = (int) (height * resizeTimes);
			/* 新生成结果图片 */ 
			result = new BufferedImage(toWidth, toHeight, BufferedImage.TYPE_INT_RGB);
			result.getGraphics().drawImage( im.getScaledInstance(toWidth, toHeight, java.awt.Image.SCALE_SMOOTH), 0, 0, null);
		}catch (Exception e) {
			System.out.println("创建缩略图发生异常" + e.getMessage());
		}
		return result;
	}
	
	public boolean writeHighQuality(BufferedImage im, String fileFullPath) {
		try{
			/*输出到文件流*/ 
			FileOutputStream newimage = new FileOutputStream(fileFullPath); 
			JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(newimage); 
			JPEGEncodeParam jep = JPEGCodec.getDefaultJPEGEncodeParam(im);
			
			/* 压缩质量 */ 
			jep.setQuality(0.9f, true); 
			encoder.encode(im, jep);
			
			/*近JPEG编码*/ 
			newimage.close(); 
			return true;
		}catch (Exception e) {
			return false;
		}
	}
	
	//等比例压缩，效果不错的代码
	public static void main(String[] args) {
		String inputFoler = "E:/P70305-153227.jpg" ;  
		/*这儿填写你存放要缩小图片的文件夹全地址*/ 
		String outputFolder = "E:/outputFolder.jpg";  
		/*这儿填写你转化后的图片存放的文件夹*/
		
		NarrowImage narrowImage = new NarrowImage();
		narrowImage.writeHighQuality(narrowImage.zoomImage(inputFoler), outputFolder);
	}
}
